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T Seidal

Publications and source records attributed to T Seidal.

At least 19 recordsLinked to original sources
PubMed2001

Interpretation and quantification of immunostains.

Despite the fact that immunohistochemistry is widely used in routine diagnostic work and is a very common part of scientific reports in pathology and cytology, its standardization still lags behind. Interpretation of immunostains should be based on microanatomic distribution of the staining, proportion of positively stained cells, staining intensity, if relevant, and cutoff levels. These parameters should be shown to be reasonably reproducible and should be clearly defined in publications. Uniformity in the setting of thresholds could probably benefit from interlaboratory control materials containing defined amounts of the target antigen. Reliable and precise quantitative immunohistochemistry requires the use of control materials containing defined amounts of the target antigen and processed alongside the specimen combined with automated computer-assisted microspectrophotometry. Application of these suggestions is hoped to improve standardization and to facilitate communication in the field of immunohistochemistry.

Humans↗
PubMed2001

Prognostic importance of DNA ploidy and p53 in early stages of epithelial ovarian carcinoma.

Patients with early stages (FIGO stages IA-IIC) of ovarian cancer continue to experience tumor relapses and they succumb due to their disease after seemingly adequate adjuvant therapy. In a series of 113 patients treated with adjuvant radiotherapy 4-6 weeks after primary surgery, the DNA content and p53 status of the tumors were studied and related to other known prognostic factors (age, FIGO stage, histopathologic type, and tumor grade). The DNA analyses were done by flow cytometry and p53 expression was studied by immunohistochemistry on formalin-fixed and paraffin-embedded tissue. DNA analyses of 103 tumors could be made and the p53 status was determined in 106 cases. Univariate analyses showed that both p53-positivity and aneuploidy of the ovarian tumors were strongly associated with tumor grade. There was also a strong association between p53 expression of the tumors and DNA aneuploidy (DNA index >1.10 and S-phase fraction >11.5%). P53-positivity and tumor grade were the only significant factors for the risk of tumor recurrence. DNA and p53 status alone were not adequate predictive factors to identify clinically relevant subgroups of patients who would benefit from adjuvant postoperative therapy. Tumor grade remains the most important prognostic factor with regard to the risk of tumor recurrence and the cancer-specific survival rate in early stage ovarian carcinoma. Overexpression of p53 also increases the risk of tumor recurrence.

Adenocarcinoma, Clear Cell↗
PubMed2000

[Unified methods for vaginal cytological diagnosis are required. Accuracy of the ASCUS respective CIN I compared].

A study is focused on the evaluation and comparison of the Bethesda ASCUS-diagnosis (Atypical Squamous Cells of Undetermined Significance) with the CIN I-classification (cervical intraepithelial neoplasia). From 1996 to 1999 2070 cases were reported as being ASCUS, which represented 2.5 per cent of 81,518 gynecological cases diagnosed during the same period. In 479 cases (23 per cent) a subsequent biopsy and/or endocervical curettage was performed. The control group was 740 (24 procent) of 3113 cases with CIN I diagnosis. Out of these two groups only those cases were selected that had undergone biopsy after either ASCUS diagnosis (135 cases) or CIN I diagnosis (740 cases). Out of the 135 ASCUS cases 25 (19 per cent) showed condylomata, 39 (29 per cent) cervical intraepithelial neoplasia (CIN I) and 20 (14 per cent) CIN II-III. No case of carcinoma was detected after histological examination. The control group of 740 cases included 102 (14 per cent) with condylomata, 208 (28 per cent) with CIN I and 118 (16 per cent) with CIN II-III. Among patients with an ASCUS diagnosis after cytology and subsequent cervical biopsy 43 per cent had cervical intraepithelial neoplasia, either CIN I or CIN II-III, as against 44 per cent in the control group. These findings indicate that ASCUS cytologically defines a group of patients with or at risk for developing of a squamous intraepithelial lesion.

Adult↗
PubMed2000

Diagnosis of gastrointestinal stromal tumor by fine-needle aspiration biopsy: a cytological and immunocytochemical study.

The diagnosis of gastrointestinal stromal tumors (GIST) is generally established on histopathologic examination of surgical specimens. The present study was undertaken to characterize the cytologic appearance of these tumors and to assess the utility of fine-needle aspirates, including immunocytochemistry for the demonstration of c-kit (CD117) and CD34, in the preoperative diagnosis. The study comprised preoperative fine-needle aspirates in three cases and aspirates performed on fresh surgical specimens in eight cases. The routinely stained smears revealed a mesenchymal cell population, predominated by spindle cells. In five of six cases a strong positivity for c-kit was demonstrated and in three of five cases a strong CD34-expression was found in the tumor cells. These results show that fine-needle aspiration appears to be a useful method for the recognition and diagnosis of GISTs or ICC (interstitial cell of Cajal) tumors.

Antigens, CD34↗
PubMed2000

Effects of inhalation of corticosteroids immediately after experimental chlorine gas lung injury.

BACKGROUND: To assess the effects of treatment with nebulized corticosteroids immediately after chlorine gas injury. METHODS: Eighteen anesthetized and mechanically ventilated pigs were exposed to chlorine gas (140 ppm for 10 minutes) and observed for 6 hours. Nine pigs were treated with nebulized beclomethasone-dipropionate 20 microg/kg (BDP group), and nine pigs were given no treatment (control group). RESULTS: All animals developed severe pulmonary dysfunction. The initial decrease in PaO2 was similar in both groups, but BDP-treated animals improved whereas control animals deteriorated (p < 0.005; analysis of variance). Pulmonary vascular resistance increased in both groups but less in the BDP group (p < 0.01). Lung-thorax compliance was better preserved in the BDP group (p < 0.01), and oxygen delivery was significantly better in the BDP group (p < 0.01). One animal died in the BDP group, as did three animals in the control group. CONCLUSION: Immediate treatment with nebulized BDP improved pulmonary and cardiovascular function after experimental chlorine gas injury.

Administration, Inhalation↗
PubMed2000

The pap-smear history of women with invasive cervical squamous carcinoma. A case-control study from Sweden.

BACKGROUND: Screening by cytology is a potentially highly effective procedure for preventing carcinoma of the uterine cervix. To elucidate any weaknesses in the screening procedure in a Swedish county where screening started many years ago, the detection of invasive cervical squamous cell carcinoma was compared to the prior cytological screening. METHODS: On the basis of the complete Pathology data files, including cytology and histology, all 112 women with invasive cervical squamous carcinoma were compared to 112 matched controls from the Swedish Population Register, regarding attendance rate and results of Pap-smears prior to the date of discovery of an invasive carcinoma in the case. RESULTS: Almost as many cases as controls had a history of pap-smear testing, but the cases had significantly more prior atypias registered. Only 16% of women with cervical carcinoma and younger than 60 years were lacking Pap-smear tests prior to the carcinoma diagnosis, but 46% had former atypias registered. More than half of them presented, however, a negative Pap-smear test less than three years before the diagnosis. Among the controls, 10% were lacking prior Pap-smears and only 9% had former atypias registered. CONCLUSION: The policy for follow-up and treatment of cervical dysplasias has to be improved in order to achieve a further reduction of the incidence of invasive carcinoma.

Adult↗
PubMed1999

Expression of c-kit (CD117) and Ki67 provides information about the possible cell of origin and clinical course of gastrointestinal stromal tumours.

AIMS: Gastrointestinal stromal tumours (GIST) were analysed to determine their immunophenotype with emphasis on the expression of CD34 and c-kit and to identify a possible cell of origin. Furthermore, the aim was to correlate clinical, histological and immunophenotypic parameters to their clinical course by means of statistical analysis. METHODS AND RESULTS: An immunohistochemical analysis was performed on 64 cases of GIST. Three of the tumours displayed an immunohistochemical phenotype compatible with the diagnosis of leiomyomatous tumour. Almost half the tumours were stained positively for CD34 and 48 of 61 tumours were positive for c-kit (CD117), a marker of haematopoietic progenitor cells, mast cells and the so-called interstitial cell of Cajal (ICC). In most of the cases, the staining was strong and evenly distributed within the tumours. Statistical analysis on 31 cases with an appropriate follow-up time, showed that the expression of Ki67 in the nuclei of the tumour cells was the most important prognostic factor. CONCLUSIONS: Judging from the results of the immunohistochemistry, there would appear to be some justification for suggesting a label of ICC tumours for these c-kit-positive tumours without any other obvious phenotype. A discriminant function analysis allowed 90.3% of patients to be correctly classified in prognostic terms from data on Ki67 and CD34 expression, grade, size and patient age.

Adult↗
PubMed1993

Primary squamous carcinoma of the thyroid--a case report.

We report a well-documented case of fatal thyroid cancer with histopathological characteristics of primary squamous carcinoma. A possible primary tumour elsewhere was excluded. The possible histogenesis of this unusual tumour and the therapy of choice are briefly discussed.

Aged↗
PubMed1993

Immunoreactivity to cytokeratins in non-epithelial cells in deep gastric ulcer.

The finding of cytokeratin positivity in non-epithelial cells in 9/15 cases of performing or penetrating gastric ulcer is reported. Two different monoclonal anti-cytokeratin antibodies were used and both produced a strong positivity in spindle and polyglonal cells in the gastric wall. These cells were often distributed near the peritoneal surface, but they were also found in central parts of the gastric wall. The cytokeratin-positive cells had no connection with the gastric mucosa, lacked epithelial features in routinely stained sections and were not positively stained by antibodies to other epithelial markers (EMA and Ber-Ep 4). Many of the cytokeratin-positive cells were also positive for vimentin. There was no evidence of malignancy in any of the cases, but cytokeratin-positive cells like those in the present study may be erroneously interpreted as infiltrating carcinoma. The true nature of the cytokeratin-positive cells was not revealed in the present study. It is concluded that cytokeratin positivity must be evaluated with care and that it is valuable to add antibodies other than anti-cytokeratins for the recognition of epithelial cell differentiation.

Antibodies, Monoclonal↗
PubMed1992

Primary chondroblastic osteogenic sarcoma of the left atrium. Case report.

A case of chondroblastic osteogenic sarcoma of the left atrium is presented. The malignant nature of the tumour was not revealed until surgery. It was considered to be nonresectable. At autopsy the tumour was found to be confined to the atrial septum. The possibility of preoperatively establishing the diagnosis and determining the extent of the tumour is discussed.

Adult↗
PubMed1991

Intermediate and fine cytofilaments in cutaneous and subcutaneous leiomyosarcomas.

The expression of fine and intermediate cytofilaments in 10 cutaneous and seven subcutaneous leiomyosarcomas was studied immunohistochemically. All the tumors contained tumor cells which showed a positive immunoreactivity for desmin in formaldehyde-fixed and paraffin-embedded sections, but none of the seven anti-desmin antibodies used alone produced a distinct positive staining in all the tumors. A lack of correspondence in terms of immunoreactivity between tumor cells and the supposed muscle of origin was observed, especially in the subcutaneous leiomyosarcomas. In all cases, antibodies to muscle-specific and smooth muscle-specific actin were found to produce a positive staining in both the tumors and the supposed muscle of origin. Vimentin was detected in 8/10 cutaneous and 4/7 subcutaneous leiomyosarcomas, while the supposed muscle of origin was positive in 3/10 and 7/7 cases, respectively. Four of the cutaneous and three of the subcutaneous leiomyosarcomas contained tumor cells which stained positively for cytokeratins, while the supposed muscle of origin showed no positivity. It thus appears that a phenotypic shift in terms of vimentin and cytokeratin expression occurs in the tumor cells of cutaneous and subcutaneous leiomyosarcomas compared with the supposed muscle of origin. It is recommended that more than one monoclonal anti-desmin antibody is used to characterize these tumor entities. It is also concluded that the immunoreactivity for muscle-specific actins in superficial leiomyosarcomas is more constant, although less specific, than that of desmin and that the demonstration of the simultaneous expression of muscle-specific actins and desmin is helpful.

Actin Cytoskeleton↗